The time taken by a man to row his boat upstream is twice the time taken by him to row the same distance downstream. If the speed of the boat in still water is 42 kmph, find the speed of the stream? September 23, 2025 by Admin A. 12 kmph B. 13 kmph C. 14 kmph D. 15 kmph ✅ The correct answer is option C. 14 kmph.